1. Field of the Invention
The present invention relates to an ink jet ink, a method for producing an ink jet ink, an ink jet recording method and an ink cartridge.
2. Related Background Art
An ink jet recording method is a recording method of applying a small ink droplet to any one of recording media such as plain paper, glossy media and the like to form an image, and has become rapidly widespread owing to reduction in its costs and improvement in its recording rate. In addition to the improved quality of the recorded image, and concurrently with the rapid spread of digital cameras, users of ink jet printers now demand to output recorded matter which are comparable to a silver halide photograph.
As a necessary requirement for a recorded matter which is obtained from an ink jet recording method and is comparable to a silver halide photograph, it is cited that both high color developability and durability of the obtained recorded matter are realized simultaneously. In particular, if a recorded matter obtained using yellow ink is left for a long period of time in a high-humidity environment, in some cases the image is susceptible to varying in color tone and fading due to migration of the coloring material in the image. That is, there is the problem that, in some cases, the durability (especially humidity resistance) of a recorded matter obtained using yellow ink is worse than that of a recorded matter obtained using cyan ink or magenta ink. In the past various technological improvements have been carried out to resolve this problem.
For example, to improve humidity resistance of a recorded matter, inks which include a coloring material having a specific structure such as C.I. Direct Yellow 173 or C.I. Direct Yellow 86 have been proposed (e.g. see Japanese Patent Application Laid-Open H02-233781 and Japanese Patent Application Laid-Open H04-233975). Inks which include a novel coloring material having humidity resistance, light resistance, moisture resistance, a hue and vividness suitable for an ink jet recording method have also been proposed (e.g. see Japanese Patent Application Laid-Open 2003-321627).